Printing mechanism



NOV. 27, 1934- F, c o 1,981,990

PRINTING MECHANISM Filed Dec. 20, 1932 2 Sheets-Sheet 1 lllllin INVENTOR Mw& lfma BY =-A1TORNEY NOV. 3 F. M. CARROLL 81,990

PRINTING MECHANISM Filed Dec. 20, 1932 2 Sheets-Sheet 2 INVENTOR 4mz to a w (a u b M N- 12345676 BCDEFGHI K MNOPQ TUYWXYZO {a A RNEY Patented Nov. 27, 1934 UNITED STATES PRINTING MECHANISM Fred M. Carroll, Yonkers, N. Y., assignor, by mesne assignments, to International Business Machines Corporation poration of New York New York, N. Y., a, cor- Application December 20, 1932, Serial No. 648,039

8 Claims.

This invention relates to accounting machines and more particularly to rotary printing drums to be used in conjunction with such machines.

The invention may be applied to a rotary alphabet printing tabulator of the type disclosed in Letters Patent No. 1,726,539, issued to applicant September 3, 1929. This patent discloses a drum carrying a pluralityof rows of pivoted type carriers each carrier having disposed thereon a plu- 0 rality of type. As the drum rotates these type carriers arrive at a predetermined printingposition successively, and suitable call mechanism located adjacent the drum may be actuated to rotate any one or the type carriers about its pivot when it reaches the printing position, causing cne of the type carried thereby to strike a paper carrying platen. Each type carrier, when actuated to print, may print from one of the several type characters mounted thereon, the platen being shifted to different positions to select the particular type from which an impression is to be made.

The platen, in the above mentioned patent. was shifted to a different elevational position for each successive rotation of the printing drum, a diflerent type carrier being selected and an impression taken therefrom at each revolution of the drum. In addition the call mechanism was located entirely externally of the printing drum which increased the bulk of the machine. Further, the types of the machine disclosed in the above mentioned patent struck the platen a receding blow. This action necessitates the use 01' additional mechanisms to restore and latch the type carriers after they have actuated to strike an impression below.

It is therefore an object of this invention to provide a simplified call mechanism for a rotary drum printing mechanism, which call mechanism is located within the drum.

Another object is to provide a novel mechanism for selectively controlling the position of a type element during an impression blow.

Another object of this invention is to provide a novel type carrier adapted to restore and latch itself in restored position under the influence of its rebound after striking the platen.

Other objects will be Zhereinaiter set forth in the accompanying specification and claims and shown in the drawings which illustrate what I now consider to be a preferred form or the invention.

In said drawings:

Fig. 1 is a detail sectional vlew showing the part of the printing elements together with the means for selecting the type carriers and the type selecting means.

Fig. 2 is a circuit diagram of the machine.

Fig. 3 is a diagrammatic view of a typical record card with its perforations.

Selection of type carriers Referring to Fig. 1, there is provided a printing drum including side members 20 (only one of which is shown), and a plurality of slotted cross bars 21 in the slots of which bars are pivotally mounted type carriers 23. Type carrier selecting magnets 24 are provided which, when energized under control of a record card, select the type carriers tobe operated. When the magnet 24 is energized it attracts its armature 25. v

The armature 25, through a push rod 26 rocks a latch 27 to free a tripping and selecting arm 28 to the action of its spring 29 which immediately rocks the arm 28 counter-clockwise into the path of the tail of a locking and actuating pawl 30 plvotally supported in the bifurcated portion of the type carrier 23. The pawl 30 is spring urged in a counter-clockwise direction about its pivot on the type carrier 23, and, due to the end 31 of said pawl abutting against a hardened strip 32 securely mounted in the cross bar 21. serves to lock the type carrier in its retracted position.

As the drum 20 rotates the tail of the pawl 30 strikes in the angle of the arm 28 formed by the left-hand edge of the arm and the head thereon rocking the pawl slightly clockwise about its pivot on the type carrier 23, thus unlocking the carrier from the cross bar 21. The spring 29 continues to hold to arm 28 in eiiective position and continued rotation of the drum 20 due to the tension of the spring 29 rocks the type carrier clockwise about its pivot into position to print.

As the drum 20 advances the tail of the pawl 30 rocks the tripping arm 28 clockwise against the tension of spring 29 to its retracted position where it is engaged and held by its latch 27. Shortly before the type strikes the platen the tail of the pawl 30 escapes the arm 28. The momentum of the advancing drum 20 and of the type carrier 23 through the coaction oi pawl 30 and arm 28 throws the type sharply into contact with the platen to take an impression therefrom on the record material. The rebound 01' the type is sufficient to restore the carrier to its normal position where the end 31 of the pawl 30 wipes by the bar 32 and assumes its locking posi-- tion to hold the type carrier 23 in its retracted position. The shock of the restored type carrier 23 striking the bar 21 is absorbed by a block of 'member slidable longitudinally thereon, the

member 35 bearing a plurality of type characters 36, 37, 38 and 39.

Selection of type In addition to the above described mechanism for effecting the selection of the type carriers by the energization of magnets 24, mechanism 'is provided to select the particular type 36 to 39, inclusive, on the carrier 23 for printing action. This selection of the type is made while the selected type'carriers are swinging toward printing pos tion and while the printing drum is in continuous rotation. The mechanism for effecting the selection of type will now be described.

One arm 42 of a selector lever 40 (Fig. 1) pivotally mounted on a shaft 41 carries an arcuate face 42a disposed in the plane of the type element 35. A spring 43 urges the lever in a counterclockwisedirection. A'cam 44, fast on a shaft 45 which rotates in synchronism with the drum 20, cooperates with a projection 46 on the other arm 47 of the selector lever 40. lhe cam 44 acts to restore the selectors 40 near the end of a cycle and releases said selector to the action of the springs 43 early in the succeeding cycle.

The selector levers 40 are positioned under the control of magnets 48 which are energized in synchronism with the counterclockwise movement of the selector lever 40, when released by the cam 44, the movement of the levers 40 being synchronous with the passage of a card by the upper brushes as will be more fully brought out later.

The free end of the selector arm 4'7 is provided with three notches 49, 50 and 51. During an operation of the machine the magnet 48 is energized rocking a latch 52 which in turn trips a pawl 53 which under the influence of a spring 54 is rocked clockwise into engagement with one of thenotches 49, 50 or 51, depending upon the time of energization of the magnet 48. If the magnet 48 is not energized the pawl 53 will not be tripped and the arm 4'7 will come to rest on a rod 55 to determine the fourth position of the selector 40. Near the end of an operation a universal bar 56 engages the pawls 53 rocking them counterclockwise to normal position, where the latches 52 under the influence of their springs 54 latch said pawls.

Thus it can be seen that the selector lever 40 has four positions, which positions, with reference to the arcuate edge 42a of arm 42, determines the printing position of the type element 35. This element slides outwardly on its carrier 23 due to the centrifugal force generated by the sharp swinging movement of the carrier 23 when tripped and rocked by its associated selecting arm 28 as above described.

Accordingly the above described mechanism determines which one of the types 36, 37, 38 or 39 will strike the platen 33 to cause the impression. It may be noted here that this selection of type is effected during one rotation of the printing drum 20 so that any one of the type upon a selected carrier 23 may be caused to print during such single rotation of the drum. There is therefore a concurrent selection of type carriers and of the type on the selected carriers for printing action. While the selector levers 40 receive a preliminary set-up, the actual selection of types occurs while the type carrier 23 is swinging to printing position under the influence of its selecting arm 28 as above described.

Referring now to Figure 2, a stack of record cards 60 is adapted to be handled and advanced in the usual manner one by one, by suitable feed rollers such as are indicated at 61. Suitable card sensing means are provided comprising a set of lower brushes 62 and contact blocks 63, and a set of upper brushes 64 and contact blocks 65. The usual and well known card picker device (not shown) is employed. The mechanism is driven by a suitable motor M.

The lower brushes 62 are spacedwith respect to the upper brushes 64 so that the 12th index point of the card will have left the upper brushes at the time the 9th index point of the preceding card is about to encounter the lower brushes 62.

Suitable cam operated contact devices 66 and 6'! are provided to control the supply of current to brushes 62 and 64 and to the circuits therefor at the proper time. Contact blocks lead to a plug board 68 having plug sockets which connect to the selector magnets 48 as illustrated diagrammatically in Figure 2. Contact blocks 63 lead to a plug-board 70 provided with multiple sockets, and the selector magnets 24 are shown connected to plug sockets '71. The usual counter magnets, indicated at '72, are provided with suitable sockets '73.

It may be stated here that only nine type carriers are provided for the different digits. No separate type carrier is provided for printing the zero and by reference to Figure 3 it may be noted that there is a combination of index positions for zero when alphabetical characters are to be printed, viz., a hole in the sixth position and a hole in the eleventh position, and it may be further noted that a different combination of perforated index points is provided for printing digital characters involving zero.

When simple numerical items are to be printed it is necessary to plug from '70 to '71 in order to bring the type carrier selector magnet 24 into circuit, and to plug all of the sockets 68 to bring the selector magnets 48 into operation. If digital characters from one to nine are to be printed the selector magnets 48 will not be energized and consequently the selector levers '40 are moved counterclockwise out of cooperative relation with the type elements 35. In this position of the levers 40, and upon operation of a selected type carrier 23, the type element 35 is thrown out-' wardly its full extent to bring the type character 36 to printing position, thus effecting a printing of all of the significant digits. Should a zero appear on the card it will be represented by a hole in the twelfth index point position and a hole in the ninth index point position. Thus the corresponding selector magnet 48 is energized to effect zero digital printing from the proper type in the row designated 37.

When numbers are to be added in the columns in which the above mentioned numerical printing is to be effected, provision must be made to prevent the erroneous adding of 9 when zero representations are printed. Associated with the armature of each of the selector magnets 48 is a pair of contacts one of which contacts is connected to a plug socket 81 and the other contact is connected by suitable conductors to plug sockets 82.

Plug connections are made between '13 and 82 to control adding, and by reason of the contacts if the letter e is to be printed,

1,981,990 erroneous adding of "9s is prevented. These contact arrangements also prevent erroneous adding from alphabetical columns, for instance, 5" will be added onto the totalizer unless proper control is provided. Should alphabetical printing in any particular column be desired, plug connections are made in the desired column between sockets 68 in order to place the selector magnets 48 in circuit. In addition connections are made between the sockets 70 and 71.

It is to be understood that the above mentioned zero printing for numerical characters by utilizing combinational representations could be obviated by providing an additional type carrier on the printing drum, but for compactness and simplicity of arrangement, the present arrangement is disclosed.

The machine is so timed that upon the passage of cards past both sets of brushes the selectors 40 are first positioned under the control of the brushes 64 encountering a hole in either the zero, 11th or 12th index positions, thus energizing the corresponding magnet 48. The type carrier selection is then efiected in the usual manner by the holes in the 9 to 1 index position passing the brushes 62, thus energizing the corresponding magnet 24. The energization of this magnet 24 releases the associated tripping arm 28 thus calling the selected type carrier 23 into action. During the movement of the carrier 23 and while it is swinging toward the platen 33, its selector lever 40 having been previously positioned, the swinging movement of the carrier throws the type element 35 into contact with the arcuate edge 42a of the lever 40 to thus select the particular type 36 to 39, inclusive, 'on the element v35 for printing.

The adding mechanism as illustrated diagrammatically in Figure 2 may be of a type similar to that disclosed in the patent to Carroll No. 1,726,539 mentioned above.

It will be appreciated that with the present improved construction and by placing the type carrier selecting mechanism within the printing drum better selecting action is effected, a more compact mechanism is presented and the number of parts necessary to the successful operations of the call mechanism has been materially reduced. The printing of the entire alphabet and of all of the digits may be effected at one rotation of the printing drum.

For this reason a record controlled machine can print alphabetical characters and add concurrently at the speed heretofore only obtainable for adding and printing numerical characters alone.

While there has been shown and described and pointed out the fundamental novel features of the invention as applied to a single modification, it

will be understood that various omissions and substitutions and changes in the form and details of the device illustrated and in its operation may be made by those skilled in the art without departing from the spirit of the invention. It is the intention therefore to be limited only as indicated by the scope of the following claims.

'What is claimed is:

1. Ina machine of the class described, the combination of a continuously rotating printing drum, a plurality of type carriers on said drum each of said carriers having a plurality of types thereon adapted to print during rotation of the drum, means located inside the drum to selectively operate the type carriers and to cause the type to shift on the carrier, and means to control the extent of movement of the type on the carriers to select the particular type for printing.

2. In a machine of the class described, the combination of a plurality of continuously rotating type carriers, type elements movably mounted on the carriers each element having a plurality of type thereon, means for locking the carriers in retracted positions, and means for selectively unlocking and operating said carriers.

3. In a machine of the class described, the combination of a plurality of continuously rotating type carriers, means for locking the carriers in retracted position, and a single means for'selectively unlocking and operating the type carriers.

4. In a machine of the class described, the combination of a plurality of continuously rotating type carriers, type elements on the carriers each element being provided with a plurality of types, means for locking the carriers in retracted positions, means for selectively unlocking and operating the carriers, and means to determine which one of the types on the carrier is caused to print.

5. In a machine of the class described, the combination of a plurality of continuously rotating type carriers, means on each carrier for locking said carrier in retracted position, and means for selectively unlocking and then operating the carriers.

6. In. a machine of the class described, the combination of a plurality of type carriers each having a multiple type element slidably mounted thereon, means for continuously rotating said carriers, said rotation tending to cause centrifugal action to displace the type element relative to a carrier, means located radially internally of the pathof rotation to select the carriers for printing action, and means located externally of the path of rotation of said carriers to control the centrifugal displacement of the type elements for selecting the particular type for printing.

7. in a machine of the class described, the combination of a rotating printing drum, a type carrier pivotally mounted on said drum, 8. locking member pivotally supported on the carrier, and means to cause the rotation of the drum to unlock and then operate the carrier.

8. In a machine of the class described, the combination of a rotating printing drum including side members joined by cross bars, normally retracted type carriers pivoted on the cross bars, means pivoted on each carrier for locking said carrier in retracted position, and tripping means to selectively unlock and then operate the type carriers.

FRED M. CARROLL. 

